In the field of medicine, diagnoses are carried out on presence or absence of diseases and the type or status thereof while medical images generated by imaging of subjects are displayed on monitors and abnormal shadows therein are observed (hereinafter referred to as image interpretation). In addition, functions are provided to display information of cases whose tests have generated images of similar characteristics to images to be interpreted, as a function to support such diagnoses at the time of image interpretation. For example, Japanese Unexamined Patent Publication Nos. 2005-065728 and 2002-230518 describe apparatuses and methods for displaying a reference image having a high degree of similarity and information such as a finding related to the reference image, according to the steps of extracting a lesion location from an image to be diagnosed (hereinafter referred to as an interpretation target image), calculating characteristic quantities representing pictorial characteristics in the extracted lesion location, and finding a degree of similarity between each of reference images stored in a database and the interpretation target image through comparison of the characteristic quantities therebetween.
The conventional apparatuses described above are useful when diagnosis is carried out on a test result (that is, an image) obtained at one time, and have achieved reasonable results. However, in actual diagnosis, accurate diagnosis may not be carried out on a test result obtained only at one time, even if information on an image having a high degree of similarity is used as a reference. In such a case, the same test is generally carried out repeatedly at predetermined intervals, for example, so that diagnosis can be carried out by observation of progression.
As reference information for diagnosing based on a result of progression observation, information on cases representing similar progression of a disease is useful. Information on cases of similar progression is not only usable for diagnosis but also helpful for planning future tests or treatments. However, the conventional apparatuses can search for only information of cases including images similar to an image obtained at one time, as has been described above. Therefore, provision of a system enabling easy extraction of information on cases of similar progression has been desired.
An object of the present invention is therefore to provide a diagnosis support system enabling search and extraction of information on cases showing similar progression.